No. 20 Disposable Scalpel with Plastic Handle, 10 Per Box/Pack, With Built-in Measuring Scale (0cm to 6cm). Sterile: These scalpels are sterilized by gamma radiation to eliminate the risk of infection. Sharp blades: The blades are made from carbon steel and are very sharp to ensure a clean cut. Plastic handle: The handle is made from plastic and is disposable. It may have a textured grip to prevent slipping during use. Measuring scale: The handle has a built-in measuring scale, in centimeters and millimeters (0cm-6cm). This allows the user to measure the length of incision or tissue to be removed.